Question

1. Name the phenomenon which causes the following change:

(b) Disappearance of camphor when exposed to air.

Answer 1

Sublimation:

• There are some substances that directly change from the solid-state to the gaseous state and from the gaseous state to the solid without passing through the liquid state.
• The substance which shows these properties are known as sublimable substances.
• The conversion of a solid substance into its vapour without passing through a liquid state is called sublimation.
• For example, camphor, iodine, dry ice (solid carbon dioxide), and naphthalene are some examples of sublimation.

Concluding statement: The process of conversion of solid to gas or gas to liquid without passing through liquid is known as sublimation.